Understanding the origins of dendrite formation and growth in LLZO solid electrolytes

Obiettivo

Rechargeable lithium-ion batteries have gained crucial importance for energy storage systems due to their high energy and power density, reliability and cyclability. Solid-state electrolytes provide a promising alternative for highly flammable conventional liquid electrolytes, as they offer high thermal stability, high conductivity and improved safety. Dendrite formation and growth through solid electrolyte is one of the main challenges, critically reducing the performance of Li batteries due to battery short circuit. However, the origins of dendrite formation and parameters affecting its growth rate are still unclear. It has been hypothesized that internal defects such as cracks, and grain boundaries serve as potential nucleation sites for dendrite formation as Li transports through solid electrolytes. The objective of Den-LLZO project is to obtain a fundamental understanding the origin of dendrite formation and growth in the vicinity of the microstructural features. Den-LLZO project aims to use atomic scale simulations to establish a mechanism map for dendrite formation in the presence of microstructural defects and to develop continuum models to predict the dendrite nucleation and growth rate in solid electrolytes. In the first phase, we perform first-principle and molecular dynamics simulations to identify when, how and to what extent different internal defects trigger dendrite formation and growth. The second phase seeks to develop predictive continuum models, informed through atomic scale simulations, for monitoring dendrite nucleation and growth in solid electrolytes. The ambitious goal of Den-LLZO project is to propose design principles for suppressing dendrite formation in solid electrolytes, resulting in improved lithium-ion battery performance and lifetime, and hence facilitated transition toward renewable energy.